US raises possibility of military response to renewed Russian aggression – Tusk

The United States has for the first time raised the possibility of a military response should Russia violate a future ceasefire agreement with Ukraine, Polish Prime Minister Donald Tusk said on Monday following a meeting of European leaders in Berlin. This was reported by NewsToday24, citing Onet.

Tusk’s comments come amid intensified diplomatic talks on ending the Russian-Ukrainian war. On 14–15 December 2025, delegations from Ukraine and the United States held negotiations in Berlin focused on a potential framework for a ceasefire and longer-term security arrangements. At the same time, European heads of state and government gathered in the German capital to present their own proposals for security guarantees for Ukraine.

Earlier, Ukrainian President Wolodymyr Zelenskyy stated that Ukraine continues to seek full membership in NATO. However, as a possible compromise, Kyiv is also considering alternative security guarantees. These include guarantees from the United States similar in nature to Article 5 of the NATO treaty, as well as commitments from European countries and partners such as Canada and Japan.

Journalists asked Tusk whether the proposed security guarantees for Ukraine could be directly compared to NATO’s Article 5, which provides for collective defence.

“That would be too strong a formulation,” Tusk said. “But for the first time, I heard from American negotiators — and Steve Witkoff was very explicit on this point — that the United States is prepared to participate in security guarantees for Ukraine in such a way that the Russians would have no doubt that an American response would be military in nature if Russia were to attack Ukraine again.”

Tusk stressed that while this approach may resemble Article 5 in certain respects, he would not directly link the two. A formal comparison, he said, could complicate further negotiations. Nevertheless, he described the declaration from the US side as exceptionally far-reaching.

The Polish prime minister emphasised that Washington’s clear willingness to take part in a system of security guarantees for Ukraine is of crucial importance. At the same time, he acknowledged that potential territorial concessions remain an open and highly sensitive issue, requiring careful consideration primarily by the Ukrainian side.

Photo -Wolodymyr Zelenskyy / Telegram